[Web4lib] Customizable web search software?

[Melissa Martinez]

Hi,
I work in a theological library where we would like to be able to provide 
our users with a way to search some of the best online websites in this 
field all at the same time.  The idea is for something similar to the way 
that Google's advanced search allows you to search within a domain, but we 
would want to search within several domains (even if all the program did was 
tell Google to search term x on domain y then term x on domain z and then 
compiled the results, that would be sufficient).  Does anyone know of a 
program that does this?  Or, if there is an online web search that could be 
customized this way and the settings saved with a password, that would be a 
good start. Thanks in advance.